2英寸氮化铝单晶应力模拟、热键合及生长研究

doi:10.16553/j.cnki.issn1000-985x.2026.0031

摘要/Abstract

摘要： 本文围绕2英寸（1英寸=2.54 cm）氮化铝（AlN）单晶的应力调控、热键合工艺及高质量厚晶生长开展计算仿真和单晶生长研究。精准揭示了不同衬底材料对AlN单晶施加的降温热应力机理，阐明金属衬底特性与晶体残余应力的内在关联，为AlN单晶生长的衬底筛选提供理论支撑；在此基础上基于仿真模拟技术，创新实现了2英寸AlN低应力热键合工艺，解决了AlN籽晶高温热键合面临的应力开裂难题；同时，结合仿真与结构优化设计成功突破厚晶生长技术，制备出厚度达10.8 mm的2英寸高质量AlN单晶，晶片（002）高分辨X射线衍射（HRXRD）摇摆曲线半峰全宽低至51.67″。

关键词: 氮化铝单晶; 应力抑制; 有限元分析; 热膨胀系数; 物理气相传输; 热键合

Abstract: This paper，focusing on the stress regulation，thermal bonding process，and high-quality thick-crystal growth of 2-inch aluminum nitride （AlN） single crystals，performed systematic computational simulations and single-crystal growth experiments. It reveals the mechanism of cooling-induced thermal stress imposed on AlN single crystals by different substrate materials，and elucidates the intrinsic correlation between the properties of metal substrates and the residual stress of the crystals，providing theoretical support for the substrate selection in AlN single-crystal growth. Moreover，relying on simulation technology，an innovative low-stress thermal bonding process for 2-inch AlN is achieved，addressing the stress-induced cracking problem encountered during the high-temperature thermal bonding of AlN seed crystals. Meanwhile，by integrating simulation with structural optimization design，the thick-growth technology is successfully broken through，and a 2-inch high-quality AlN single crystal with a thickness of 10.8 mm is fabricated. The full width at half maximum （FWHM） of the （002） high-resolution X-ray diffraction （HRXRD） rocking curve of the wafer is as low as 51.67″.

Key words: AlN single crystal; stress control; finite element analysis; thermal expansion coefficient; physical vapor transport; thermal bonding

中图分类号:

O782

高飞, 辛倩, 王英民, 程红娟, 王增华. 2英寸氮化铝单晶应力模拟、热键合及生长研究[J]. 人工晶体学报, 2026, 55(6): 878-885.

GAO Fei, XIN Qian, WANG Yingmin, CHENG Hongjuan, WANG Zenghua. Stress Simulation, Thermal Bonding, and Growth of 2-Inch Aluminum Nitride Single Crystals[J]. Journal of Synthetic Crystals, 2026, 55(6): 878-885.

图/表 4

图1 不同衬底材料热应力模拟。W、Re、Ta、TaC和AlN的热膨胀系数（a）及热应变（直径收缩ΔL/L0）曲线与温度的关系（b）；（c）冷却后不同衬底的氮化铝晶锭的应力分布；（d）径向应力与晶锭半径的关系；（e）轴向应力与晶锭厚度的关系

Fig.1 Thermal stress simulation of different substrates. Temperature dependence of thermal expansion coefficients （a） and thermal contraction （ΔL/L0） curves （b） for W，Re，Ta，TaC，and AlN；（c） stress distribution of AlN boule with different substrates after cooling；（d） radial stress versus boule radius；（e） axial stress versus boule thickness

图2 AlN籽晶热键合及应力模拟。（a）氮化铝籽晶热键合到钨衬底上的示意图；（b）应力模型的网格划分；一步降温（c）和分步降温（d）氮化铝籽晶热应力分布图；（e）无裂纹热键合氮化铝籽晶

Fig.2 Thermal bonding and stress simulation of AlN seed. （a） Schematic diagram of thermal bonding of AlN seed onto W substrate；（b） meshing of the computational model； residual stress distribution of AlN seed undergoing one-step （c） and stepwise cooling processes （d）；（e） crack-free thermal bonded AlN seed

图3 AlN单晶降温应力模拟。（a）不同直径氮化铝晶锭的降温热应力分布图；（b）轴向应力与晶锭厚度的关系；（c）径向应力与晶锭半径的关系；（d）50 mm AlN不同厚度位置径向应力分布曲线

Fig.3 Thermal stress simulation of AlN single crystal. （a） Cooling thermal stress distribution of AlN boule on W substrate with different diameters；（b） axial stress versus boule thickness；（c） radial stress versus boule radius；（d） radial stress distribution at different thickness positions of ?50 mm AlN

图4 2英寸AlN单晶生长结构及生长结果。（a）2英寸AlN单晶生长装置示意图及热场结构模拟图；2英寸AlN单晶（b）及单晶衬底（c）光学照片；（d）单晶衬底偏振光照片；（e）原子力显微照片；2英寸AlN单晶衬底的（002）HRXRD摇摆曲线半峰全宽（f）及Raman Mapping（g）

Fig.4 Growth structure and result of 2-inch AlN single crystal. （a） Schematic diagram of the PVT device and optimized thermal distribution for growing 2-inch AlN single crystal； as grown 2-inch AlN single crystal （b） and wafers （c）；（d） crossed polarizer image；（e） AFM image； HRXRD （002） rocking curve （f） and Raman Mapping （g） for 2-inch AlN wafer

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